Radio reflector marker



Oct. 9, 1951 c w, HANSELL 2,570,549

RADIO REFLECTOR MARKER Filed April 18, 1947 I N V EN TOR. Clare]: 08 W Zane/e]! Patented Oct. 9, 1 951 RADIO REFLECTOR MARKER Clarence W. Hansell, Port Jeflerson, N. Y., assignor to Radio Corporation of America, a; corporation of Delaware Application April 18, 1947, Serial No. 742,305

4 Claims.

This invention relates to a radio reflector marker for radar systems and is particularly adapted to retain radar reflectors above the surface of a relatively large body of water.

One of the problems encountered in radar marker type reflectors is to locate them at a substantial height above the surface of the water.

According to my invention, the reflectors are held at a desired height by a balloon which has an attached float and an anchor. The balloon is preferably of a type which will operate as a kite as well as a balloon, so that it will not be pushed down into the water by strong winds.

This invention will best be understood by referring to the accompanying drawings, in which:

Fig. 1 is an elevation of the radar reflector system of this invention; and

Fig. 2 is a sectional detail of the gas container float which is provided with a water soluble band to inflate, and a second water soluble band to release the balloon.

Referring now in detail to Fig. l of the drawing, the guide balloon I is provided with anchor ropes 2 and 3 to which radio reflectors 4 and 5 are attached. The lower portions of reflectors 4 and 5 terminate in a Y-shaped connection member I5 to which other reflectors I and 8 are secured, these reflectors being disposed in a different angular position to that of reflectors 4 and 5. A connection member 9 joins reflectors I and 8 to another reflector ID, the lower portion of which connects to reflectors II and I2 which are disposed in a difierent angular position with ,respect to that of reflectors I, 8, 9 and I0. Link I3 connects reflectors II and I2 to reflector I4.

, A balloon cord I5 connects the lower part of reflector I4 with a level adjuster float I6. A cord I1 connects the lower portion of level adjuster float I8 with a lead weight I8 to which is secured a sea anchor I9 which is preferably made with a folded frame of spring material which opens up to form a cloth cone 20.

The reflecting wires 4, 5, I, 8, II), II, I2 and I4 are attached to the balloon or the cord, or both, and are so positioned as to receive radiant energy of any polarization from and reflect the same in any direction. Preferably, each reflector wire should be adjusted in length for one-half wave resonance to the frequency of the radar equipment.

Referring now in detail to Fig. 2 of the drawing, the balloon I is provided with a rubber check valve 2| and a tubular depending portion 22. The level adjuster float I6 is preferably in the form of a hollow spherical or cylindrical member and serves as a gas container. The upper portion of float I6 is provided with a valve stem 23 with apertures 24 for releasing the gas when it is desired to inflate the balloon. The balloon and float I6 are assembled with the depending portion 22 telescoping over the valve stem 23 and thus covering the apertures 24. Surround ing the depending portion 22 is a water soluble band 25 which is released to inflate the balloon. A second water soluble band 26 is positioned just below band 25 and is made sufficiently large to require a longer time for releasing the balloon after it is inflated by the gas within container IS.

The pressure of the gas in the depending rubber portion 22 forces the balloon loose from stem 23 after band 26 is dissolved in the water. As the line cord I5 is attached to the float I6, balloon I, and the reflectors, this permits balloon I to .rise to a desired height. The balloon should follow the design of a kite type balloon generally used as balloon barrages for the protection of ships and cities. The anchor cord, between the balloon and the anchor I9 should be of strong waterproof insulating material to which the reflecting wires are attached.

In the operation of this device, the whole assembly is preferably placed in a hermetically sealed can which can be opened as needed, and the balloon, reflector and anchor assembly taken out and dropped through a hole or tube from an airplane into the water. When float I6 hits the surface of the water, the water splashes up over the surface of this float and strikes the first water soluble band 25 which disintegrates and causes the rubber depending portion 22 to expand enough to open apertures 24, which in turn release the gas held under pressure within container I6. The gas then enters balloon I from the rubber check valve 2I and inflates the guide balloon which tries to rise when the gas has fully inflated it. The second water soluble band 26, which is larger and therefore takes a longer time to disintegrate, releases the hold between stem 23 and balloon I after it is fully inflated by the gas within container I6. Thus, the automatic balloon inflater and release mechanism permits balloon I to rise to a desired height, taking with it the balloon cord I5 and the radio reflectors which are attached thereto.

The balloon type of radar reflector of this invention can be packed as a small, light weight unit which can be handled easily.

One application for the marker is to fix the from said float after it has been inflatedto cause said balloon to rise with said reflectors to a 7 height above the surface of said body of water to receive radiant energy waves of any polarization from and reflect the same in any direction.

4. A radar device adapted to be dropped into a body of water, comprising a balloon, a line cord secured to said balloon, a plurality of metallic reflectors, each of said reflectors being linked flectors, a float secured to said mooring line to I support said balloon and reflectors above the surface of a body of water to receive radiant energy waves of any polarization from and reflect the same in any direction, inflating means on said float comprising an automatic balloon inflator having attached thereto a water soluble band which releases gas to inflate the balloon, and a second soluble band secured to said balloon and float which releases the balloon after it has been inflated. 1

2. A radar balloon reflector comprising a kite type balloon having a mooring line secured thereto, a plurality of metallic reflectors secured to said balloon and said mooring line, said reflectors each being substantially a half wave long at the operating frequencies of associated radar equipment, said reflectors being arranged in-a row and disposed at different angular positions with respect to adjacent reflectors to receive radiant energy of any polarization from and reflect energy in any direction, a float, a weight and a sea anchor secured to said mooring line, inflating means arranged on said float comprising an automatic balloon inflator having a water soluble band arranged to release gas to inflate said balloon, and a second water soluble band secured to said balloon and float and arranged to release the balloon after it has been inflated.

3. A radar device adapted to be dropped into a body of water, comprising a balloon, a line cord secured to said balloon, a plurality of metallic reflectors, each of said reflectors being linked together and disposed in a row at different'angular positions with respect to adjacent reflectors, the reflectors at one end of the row being secured to said balloon and the reflectors at the other end of the row being secured to one end of said line cord, a float containing gas secured to the other end of said line cord, inflatin means on said float comprising an automatic balloon inflator having a water soluble band to release said gas to inflate said balloon, and further water soluble band means on said float to secure said balloon to said float and to release the balloon together and disposed in a. row at different angum positions with respect to adjacent reflectors,

the reflectors at one end of the row being secured to said balloon and the reflectors at the other endof the row being secured to one end of said line cord, a float containing gas secured to the 9 other end of said line cord, inflating means on said float comprising an automatic balloon in- 1 flator having a water soluble band to release said gas to inflate said balloon, and further water soluble band means on said float to secure said balloon to said float and to release the balloon from said float after it has been. inflated to cause said balloon to rise with said reflectors to a height above the surface of said body of water to receive radiant energy waves of any polarization from and reflect the same in any direction, and anchor mean secured to said float to confine said balloon and said reflectors in a desired position on the surface of saidbody of water.

CLARENCE W. HANSELL.

REFERENCES orrEn The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date D. 143,998 Shreeve et al. Feb. 26, 1946 579,548 Pierce Mar. 23, 1897 827,350 Crofiord July 31, 1906 978,378 'Ingaramo Dec. 13, 1910 1,650,461 Nilson Nov. 22, 1927 2,192,450 Miller Mar. 5, 1940 2,310,017 Canon-ct al. Feb. 2, 1943 2,323,064 Justfleld June 29, 1943 2,361,177 Chilowsky Oct. 24, 1944 2,380,587 Fenton July 31, 1945 2,392,199 Steiger Jan. 1, 1948 2,409,166 Track et al Oct. 8, 1946 2,422,337 Chilowsky June 17, 1947 2,462,102 Istvan Feb. 22, 1949 2,470,783 Mead May 24, 1949 FOREIGN PATENTS Number Country Date 4,475 Great Britain Sept. 19, 1883 6,266 Great Britain Mar. 12, 1914 

